A/c Problems.

In having trouble with my a/c. Apparently it is leaking from my high side service port. I went to advanced auto parts and got the part to replace it. The problem is that I cannot find a socket/wrench that will fit it. I have tried 9/16 and it is too small an 5/8 is too big. I have also tried metric. 14mm is too small and 15 mm is to big. From my understanding, this piece is soft aluminum and will strip/round off very easily. So has anybody taken this piece off and what is the best way in doing so?

I got a Schrader valve and went to take it out but there is a different type of valve in my truck. That's why I'm replacing the whole thing. It's only $5 but i don't know the best way to take it off. Thinking about taking a pair vise grips to take it off but need a better way to put the new one on

I got a Schrader valve and went to take it out but there is a different type of valve in my truck. That's why I'm replacing the whole thing. It's only $5 but i don't know the best way to take it off. Thinking about taking a pair vise grips to take it off but need a better way to put the new one on 1995 Ford F-150 302